A six-sided number cube is to be rolled 30 times. How many times do you expect to roll on an even number?
There are three even numbers on a six-sided number cube: 2, 4, and 6. Therefore, the probability of rolling an even number on any given roll is 3/6 or 1/2.
If we roll the cube 30 times, we can expect to roll an even number approximately 15 times, based on probability.
Expected number of even rolls = probability of rolling an even number x number of rolls
Expected number of even rolls = (1/2) x 30 = 15
prob(even) = 1/2
so out of 30 tries , we would expect to get 15 evens
To determine the number of times you can expect to roll an even number on a six-sided number cube rolled 30 times, you need to calculate the probability of rolling an even number and then multiply it by the total number of rolls.
A six-sided number cube has three even numbers (2, 4, and 6) and three odd numbers (1, 3, and 5). Therefore, the probability of rolling an even number in a single roll is 3/6 or 1/2.
To find the expected number of times you will roll an even number, multiply the probability of rolling an even number by the total number of rolls. In this case, the total number of rolls is 30.
Expected number of even rolls = (Probability of rolling even) * (Total number of rolls)
= (1/2) * 30
= 15
Therefore, you can expect to roll an even number approximately 15 times out of 30 rolls.